Abstract

Genetic analysis using the fission yeast has provided a powerful methodology to investigate the eukaryotic cell cycle and its control. The onset of M-phase in fission yeast is controlled by a regulatory gene network which activates the p34<latex>$^{\text{cdc}2}$</latex> protein kinase encoded by the cdc2<latex>$^{+}$</latex> gene. The coupling of M-phase to the completion of S-phase also works through p34<latex>$^{\text{cdc}2}$</latex>. A similar network is operative in vertebrate cells. Future work will focus on the controls regulating onset of S-phase and on the mechanisms by which a cell duplicates itself in space during division.